Also here is a link explaining the different grades, what they mean, and the classes that are included.

2. No you must include them in the family section. It doesn't have to be extensive. Just list their parents and their siblings (if they have any), their occupations, age, and blood status. Here is an example:

3. You may have been looking at the old information on how the game works. You can choose whichever House you feel fits your character best. In case you were looking at the wrong info thread here is a link to the most up to date game information.

If you have any more questions you can post them here or PM Flower and I.